Well, I guess this is a matter of personal experiance.

I've worked with Verizon in the past setting up DSL and had problems - but they've done some updating and now they seem to be doing well.

I have a friend who is on DSL and has great speed - sometimes even faster than me and I'm on cable. Other friends who are farther away from the switching station have a terrible slow connection.

I'd look into you proxemity to the station for DSL. I've never had a problem with a cable install, though - and generally always good speeds.